• The Journal of the Korea Contents Association
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• v.18 no.12
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• pp.456-467
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• 2018

This study analyzed the repeated causes of policy failure focusing on Yangyang International Airport cases. Yangyang International Airport, which opened in 2002, was built with about 360 billion won, but it is considered as a representative example of policy failure of local airports. According to the policy failure theory, the failure factors of Yangyang International Airport are anlyzed by rationalistic, political, and environmental complexity viewpoint. The results are as follows. First, from a rationalist point of view, Yangyang Airport failed to achieve the policy goal of securing passengers and revitalizing local economy, This is due to the pressure of politics and the lack of geographical infrastructure. Second, the failure of the stakeholders to resolve conflicts in the flow of politics can be seen as the conflict between the airline and the airport, and the failure to reconcile conflicts between the government and the airports on the low cost airline permits and subsidies. Third, from the viewpoint of environmental complexity, Yangyang International Airport can be regarded as a failure to adapt to environmental changes such as the opening of nearby expressways and railway lines, and the sharp decline of Chinese tourists. This study sugeests the establishment of an independent organization that can prevent unreasonable business promotion by politics in the case of large scale national projects, the linkage with the surrounding infrastructure and related businesses in the case of transportation facilities such as airports and railways, and institutionalization of cooperative governance for coordinating conflict among stakeholders.

• Applied Chemistry for Engineering
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• v.30 no.3
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• pp.384-388
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• 2019

In winter season, the snow and ice accretion on the bottom of the high speed railway rolling stock and boogie part has fallen at a high speed from the ballast section (gravel section for the transmission of the rolling stock load received by sleepers and fixing sleepers), causing the gravel to be scattered, thereby damaging the railway rolling stock structures and facilities. In order to solve these problems, the gravel scattering prevention net, manual de-icing, and movable hot air machine were used, but their efficiency was low. For the more efficient de-icing than ever before, an optimum material for de-icing fluid for high speed railway rolling stock was developed by evaluating the ice melting capacity, kinematic viscosity, evaporation of the material used as a chemical de-icing fluid. Four kinds of organic acid salts (sodium formate, sodium acetate, potassium formate and potassium acetate) and two different alcohols (propylene glycol, glycerol) were used as evaluation materials. Potassium formate, potassium acetate, and propylene glycol had similar ice melting capacities in the indoor test, but the propylene glycol showed the best ice melting capacity in spraying the system simulation test. This is because the kinematic viscosity of propylene glycol was 2.989029 St, which is higher than those of other materials therefore, it could stay longer on the ice and de-icing. In addition, potassium formate and potassium acetate were difficult to be used since the crystals precipitated and adversely affected the appearance of the rolling stock. The propylene glycol is the most optimum as an de-icing fluid for the high speed railway rolling stock.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.1
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• pp.98-108
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• 2013

The number of Hi-Pass lanes became 793 lanes at 316 expressway tollgates in 2011 due to the increase in the Hi-Pass use. In spite of the increase in the number of Hi-Pass lanes, there have been increased potential risks in tollgates where vehicles using a Hi-Pass lane must weave with other vehicles using a TCS lane. Therefore, there is a need for study on the safety in tollgates. To this end, this study aims at developing a methodology to evaluate the performance measures of diverse location countermeasures of Hi-Pass lanes in an efficient and systematic way. This study measured the mobility, safety and the convenience of installation and operation of Hi-Pass lanes using a microscopic traffic simulation tool, the surrogate safety assessment model and survey. In addition, this study aggregated the above three performance indexes using weight factors estimated using the AHP technique. For the test site, Dongsuwon interchange was selected. After building the microscopic traffic simulation model for the test site, the location countermeasures of Hi-Pass lanes applicable to the test site were compared with each other in terms of the mobility, safety and installing and operating convenience. As a result, there has been no apparent difference in mobility index based on delays. However, the countermeasures where Hi-Pass lanes are located in inside lanes generally showed better safety performance based on the number of conflicts. In addition, countermeasures with neighboring Hi-Pass lanes were favorable in terms of the safety and the convenience of installation and operation. The methodology proposed in this study was found to be useful to support decision makings by providing critical and quantitative information regarding the mobility, safety and the convenience of installation and operation.

• Journal of Chest Surgery
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• v.36 no.4
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• pp.229-241
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• 2003

Background:Autogenous vein is the preferred vascular graft for patients who require coronary artery bypass surgery or peripheral arterial bypass surgery. When an autogenous vein is not available, an allograft saphenous vein can be used as an alternative conduit. Although arterial homograft has been under investigation since the beginning of this century, the viability of endothelial cells and the optimum mode of storage for the venous and arterial allografts is controversial. In addition, with the recently gained knowledge of vascular endothelial functions, such as the production of nitric oxide or thrombomodulin, the viability and antigenicity of endothelial cells are being studied again. The purpose of this study was to evaluate the viability of endothelial cells in the preserved human saphenous veins. Material and Method: The veins were stored in a $4^{\circ}C$ RPMI (Roswell Park Memorial Institute) 1640 solution including 10% fetal calf serum, for one, three, five, seven or fourteen days. After the completion of the storage period, the veins were divided into two groups: Group I: studied immediately at $4^{\circ}C$ (cold) storage (I-1, I-3, I-5, I-7, I-14), and Group II: studied after storage at $-196^{\circ}C$ liquid nitrogen tank (cryopreservation) in an RPMI 1640 solution containing 10% DMSO for two weeks (II-1, II-3, II-5, II-7, II-14). Light microscopy and scanning electron microscopy (SEM), frypan blue exclusion testing, and thrombomodulin immunohistochemistry were performed. Result: In a morphometric study using SEM, there was statistically significant increase in Gundry Score in Groups I-7, I-14, II-5, II-7, and II-14 and showed cellular destruction (p<0.05). In the thrombomodulin immunohistochemistry study, there was reactivity in Groups I-1, I-3, and I-5, but the cryopreserved group revealed decreased reactivity (p<0.05). The trypan blue exclusion testing also showed superior viability in cold storage Group I. Conclusion: Venous allografts preserved in a $4^{\circ}C$ RPMI 1640 solution showed well preserved endothelial cellular integrity and thrombomodulin expression at up to seven days of preservation. Although cryopreservation of venous allografts stored in 10% DMSO -RPMI 1640 solution maintained the endothelial cellular structure on SEM, immunohistochemistry from the thrombomodulin and trypan blue exclusion testing showed decreased viability, It remains to be seen whether the decreased thrombomodulin reactivity could be restored, and what the nature to the relationship is between thrombomodulin and long-term patency of allografts.

• Journal of Chest Surgery
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• v.41 no.1
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• pp.34-40
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• 2008

Background: Off-pump coronary artery bypass grafting (OPCAB) shows fewer side effects than cardiopulmonary by. pass, and other benefits include myocardial protection, pulmonary and renal protection, coagulation, inflammation, and cognitive function. We analyzed the clinical results of our cases of OPCAB. Material and Method: From May 1999 to August 2007, OPCAB was performed in 100 patients out of a total of 310 coronary artery bypass surgeries. There were 63 males and 37 females, from 29 to 82 years old, with a mean age of $62{\pm}10$ years. The preoperative diagnoses were unstable angina in 77 cases, stable angina in 16, and acute myocardial infarction in 7. The associated diseases were hypertension in 48 cases, diabetes in 42, chronic renal failure in 10, carotid artery disease in 6, and chronic obstructive pulmonary disease in 5. The preoperative cardiac ejection fraction ranged from 26% to 74% (mean $56.7{\pm}11.6%$). Preoperative angiograms showed three-vessel disease in 47 cases, two-vessel disease in 25, one-vessel disease in 24, and left main disease in 23. The internal thoracic artery was harvested by the pedicled technique through a median sternotomy in 97 cases. The radial artery and greater saphenous vein were harvested in 70 and 45 cases, respectively (endoscopic harvest in 53 and 41 cases, respectively). Result: The mean number of grafts was $2.7{\pm}1.2$ per patient, with grafts sourced from the unilateral internal thoracic artery in 95 (95%) cases, the radial artery in 62, the greater saphenous vein in 39, and the bilateral internal thoracic artery in 2. Sequential anastomoses were performed in 46 cases. The anastomosed vessels were the left anterior descending artery in 97 cases, the obtuse marginal branch in 63, the diagonal branch in 53, the right coronary artery in 30, the intermediate branch in 11, the posterior descending artery in 9 and the posterior lateral branch in 3. The conversion to cardiopulmonary bypass occurred in 4 cases. Graft patency was checked before discharge by coronary angiography or multi-slice coronary CT angiography in 72 cases, with a patency rate of 92.9% (184/198). There was one case of mortality due to sepsis. Postoperative arrhythmias or myocardial in-farctions were not observed. Postoperative complications were a cerebral stroke in 1 case and wound infection in 1. The mean time of respirator care was $20{\pm}35$ hours and the mean duration of stay in the intensive care unit was $68{\pm}47$ hours. The mean amounts of blood transfusion were $4.0{\pm}2.6$ packs/patient. Conclusion: We found good clinical outcomes after OPCAB, and suggest that OPCAB could be used to expand the use of coronary artery bypass grafting.

• Tuberculosis and Respiratory Diseases
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• v.57 no.4
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• pp.358-363
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• 2004

Background : Photodynamic therapy (PDT) involves the use of photosensitizing agents for treatment of malignant disease. PDT is approved by the U.S. Food and Drug Administration for the endobronchial microinvasive nonsmall cell lung cancer and for palliation in patients with obstructing tumors. We report our experience and results of PDT in lung cancer. Method : Ten patients with lung cancer who were diagnosed in Chosun university hospital by histologic confirm through bronchoscopy were included between August 2002 and May 2003. The photosensitizer (Photogem$^{(R)}$, Lomonosov institute of Fine Chemical, Russia/dose 2.0 mg/kg body weight) was injected 48 hours prior to the PDT session. For PDT with the photosensitizer (Photogem$^{(R)}$), Diode LASER system (Biolitec Inc., Germany, wavelength; 633nm) were used. PDTs were done at 48-72 hours after photogem injection. Follow up bronchoscopy and chest X-ray or thorax computerized tomography were done for evaluate PDT response. Results : 9 of 10 patients with endobronchial obstruction showed partial remission with bronchus opening after PDT. Direct reaction of the tumor to PDT was similar in despite of its localization. It was as follows; edema, hyperemia, in-situ bleeding, fibrin film occurrence. Any other complications such as sunburns of skin, inflammation within the PDT zone were not occurred by the end of the fourth week. Conclusion : In the advanced endobronchial disease, PDT has been shown to be useful in treating endobronchial tumors that are causing clinically significant dyspnea or are likely to progress and lead to further clinical complications, such as postobstructive pneumonia.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.273-286
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• 2013

Recently, due to problems with subway and bus operations, a need has emerged for a solution such as the introduction of an Advanced Transit System. In several municipalities, systems have been introduced using light rail as AGT urban aesthetics construction. There is high inhibition and civil cases are delayed by more environmentally friendly and accessible remedies. For the purpose of this study, Changwon city would be transformed to have an environmentally friendly transportation system such as a tram with an overview. Features, advantages, and disadvantages are analyzed, and systems are established the existing public transport routes by transfer system. Changwon city's tram plan is first step in open in year 2018, and second step with the opening goal of the year 2021, and the total line length of 33.9 km, the station will be built in the 38 locations. and also in 2011 a feasibility study, evaluated a low economic as B/C to 0.88, but it evaluated the high value of the policy analysis as AHP to 0.502. However, introduction of a tram project that should precede the as following condition. The first step in Changwon city's tram plan would be as follows : The introduction of the tram system would demand traffic management along with a restructuring of the bus system, and the tram system would be selected for domestic realities. Secondly, the introduction of trams would comprehend the advanced traffic composition in accordance with the consensus of the citizenship, and a legal system should be established for the introduction of the trams.

• The Journal of the Korea Contents Association
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• v.15 no.7
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• pp.12-20
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• 2015

The subway is one of the representative urban public transportation systems. Since its being opened in 1974, the Seoul Subway has been continually extended, and new lines are being added in the metropolitan and outskirt areas, even at present. As a result, the numbers of transfer stations and transfer sections have been significantly increased, making the usage of the subway system more and more complicated. In the transfer stations with big floating population and overlapped flows of traffic in the subway, passengers want their movements to be more precise and faster, without taking the wrong trains by mistake. Therefore, the visual information system for the subway inside the stations is extremely important. At the same time, the visual information system is required to be easy to understand and use, even if the passengers do not have previous experience of using the subway. In this research we studied the problems existing in the visual information system which is currently working in the subway system, and suggest the direction of the improvement of the subway service based on our studies. This research was mainly performed at Sindorim Station, one of the busiest stations in Seoul Subway with huge floating population and complex transfer sections. The purpose of this research is the investigation of behavioral and recognitive characteristics of passengers in the transfer sections through preceding research and qualitative analysis, to draw the direction for future improvement of the current system and suggest the improved experience of using the subway system.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.161-168
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• 1985

The 38 typical profiles representing volcanic ash soils (VAS) in Korea were subjected to multiple regression analysis to determine the relative contribution of organic matter (OM) and clay content to total cation-exchange capacity (CEC). This study, also, was examined the soil characteristics of VAS. VAS in Korea could be classified into 3 Orders, 5 Suborders, 8 Great groups, 15 Subgroups, 23 Families, and 38 Series. Total area of VAS was 139, 162ha and the most of them occured in Jeju Island. Simple correlation coefficients showed significance relations at OM-CEC and clay-CEC in top-soil of VAS. The partial regression coefficients indicated that CEC for each gram of OM as calculated to be 0.46 and 0.40 me per of topsoils for the black volcanic ash soils (BVAS) and the very dark brown volcanic ash soils (VDBVAS), respectively. The clay contributions of topsoils for BVAD and VDBVAS were 0.11 and 0.19 me. The standard partial regression coefficients appeared that OM content of topsoil for BVAS and VDBVAS was 2.97 and 1.23 times as important as clay content in predicting CEC.

• Journal of Korean Society of Transportation
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• v.23 no.7 s.85
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• pp.17-33
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• 2005

Highway design speed is a very important design element which determines highway design level. When determining highway design speed, one would estimate it utilizing the most likelihood of design speed and vehicle operating speed relationship. Existing operating speed prediction models only include highway geometric characteristics and their impacts on speed, which usually can not consider the impact of highway design speed on surrounding roadway environment and land use pattern. If this happens, excessive highway construction cost and huge environmental impact can occur. In this research project, a new vehicle operating speed prediction model was developed which can reflect the effect of surrounding roadway environment into vehicle speed prediction. The followings are the research findings : Firstly, highway terrain types and land use pattern on national roads were classified and integrated into drivers' visual recognition pattern. This was performed using a data management software. Secondly, the developed highway terrain types and land use pattern were related to vehicle speeds and it was found that there were significant statistical differences among vehicle speed for each different terrain and land use pattern. Thirdly. the General Linear Model analysis was employed to analyze the effects of highway geometric features, terrain types, and land use patterns. For two-lane highway and four-lane highway tested in this research project, it was found that R squares were 0.67 and 0.85, respectively. Additionally an optimal highway design speed range table, based on this research project. was proposed for practical use. This table can be reliably used on South Korean national road design, but discretion is required for applying this table to other types of highways including provincial roads and municipal roads.